Participants

Intervention

The n-3 PUFA supplementation group consumed a daily dose of DHA (800 mg) and EPA (a maximum amount of 225 mg) for 3 years. The placebo group received identical capsules comprising liquid paraffin oil.

Measurements

Linear mixed-model repeated-measures analyses were used including baseline, 6, 12, 24 and 36-month follow-up data to assess between-group differences in the change in eight cognitive tests over 36 months.

Results

There was less decline on the Controlled Oral Word Association Test (COWAT) in the n-3 PUFA supplementation group compared to placebo (p = 0.009; between group mean difference over 36 months, 2.3; 95% CI, 0.6,4.0). No significant differences for any of the other cognitive tests were found, including other tests of executive functioning, although, numerically all results were in favour of the n-3 PUFA supplementation.

Conclusions

We found some evidence that n-3 PUFAs might be beneficial for the maintenance of executive functioning in older adults at risk of dementia with low omega-3 index, but this exploratory finding requires further confirmation. A larger specifically designed randomised controlled trial could be merited.